Patient signal dispatcher

ABSTRACT

In various medical electrical apparatus a patient&#39;&#39;s clinical information is entered, transmitted, and stored electrically. Accompanying this clinical data is information as to the patient&#39;&#39;s identity, e.g., name, age, when and where the clinical data was taken, etc. The invention is a novel and improved apparatus for, and a method of, entering patient identification information. The information is entered manually, stored in a memory, the stored information is displayed to an operator and then added to the clinical information.

United States Patent 1191 V elman et al. 1 51 A r. 1973 1 PATIENT SIGNALDISPATCHER 3,469,240 9/1969 Ryden 340/1715 I 3.406387 10/1968 Werme340/1725 X [75] Inventors' gf ti gs z g; 3,166,636 1/1965 Rutland et al178 24 1 of Primary ExaminerRaulfe B. Zache 73 Assignee: ChromalloyAmerican Corporation, ArwmeyCurtis. Morris& Safford New York, NY [57]TRACT [221 Filed: Nov. 9, 1970 ln various medical electrical apparatus apatients [2] I Appl- 87,784 clinical information is entered,transmitted. and stored electrically. Accompanying this clinical data isinfor- 52 us. (:1 ..340/172.s nation as to PatientS idem. name [51 Int.Cl. 606i 3/00 when and where the clinical data was taken The 58] Fieldof Search I I 340/172 78/24 invention is a novel and improved apparatusfor, and a method of, entering patient identification information. [56]References CM The information is entered manually, stored in a memory,the stored information is displayed to an UN D S A S TENTS operator andthen added to the clinical information.

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ill iii q llli 3 PATIENT SIGNAL DISPATCHER The invention relatesgenerally to medical electronics and more particularly to methods andmeans for entering information about the identity of a patient whichaccompanies clinical information about the patient.

In the field of medical electronics, clinical information about apatient, and identification information about the same patient althoughstored together, originate from separate sources. For example, in thetaking of an electrocardiogram, the electrocardiogram machine may beconnected to a transmission line, for transmission of theelectrocardiogram information to a remote recorder or diagnosticcomputer. The clinical information is taken directly from the leadsattached to the patient. The patient identification information, i.e.which patient the leads are attached to, is entered by a technician. itis essential that the technician enter the proper patient identificationinformation, for if the wrong patient identification information isentered, the record or diagnosis may then be applied to another patient.The consequences of patient mis-identification are grave. in extremecases, failure to connect the clinical information with the properpatient may produce lack of proper medication or treatment; or mightproduce a medication or treatment for a patient who does not require it;and in extreme cases this may prove fatal. It is, therefore, of graveimportance that the patient identification information that accompaniesclinical information always identify the correct patient.

The clinical information is most often automatically produced fromsensing electrodes connected to the patient. The identificationinformation is almost always entered manually by a technician such as bypunching a keyboard. It is important to minimize any error in the entryof patient identification information by the technician. The presentinvention is a method of and means for reducing the human error inentering patient identification information.

A separate but additional problem in medical electronics has to do withthe efficient use of the electronic equipment. Electrical recording andelectrical transmission of medical information is relatively fast. Agreat deal of information can be transmitted or recorded in a very shortperiod of time. The manual entry of information, such as by atypewriter, or pushing buttons on a telephone is relatively slow. It istherefore not efficient to operate most medical electrical devices in arecording or transmitting mode with a manual input. The presentinvention has the further advantage of overcoming the inefficienciesassociated with manual inputs by provided means for entering the patientidentification information into a temporary memory, and when therecording or transmitting device is ready to receive the information, itis automatically entered into the recording or transmitting device at arapid pace, which is comparable with the speed of the device.

The present invention provides a means and method of efficientutilization of electronic recording and transmission facilities used inmedical electronics.

Heretofore, in a specific example, it has been common when taking anelectrocardiogram for transmission over a commercial telephone line to aremote recorder or diagnostic center, to add to the electrocardiogramclinical information (which is recorded directly from the patient) as tothe patient's hospital identification number, his date of birth, thedate and hour on which the recording is being made, patient height,weight and sex, etc. Heretofore, this identification information wastaken from the patient, or from his chart and noted by the technician.After connecting the leads and setting up the transmitting portion ofthe ECG machine, the technician would dial on a telephone into theremote recording station, which for example, might be in a hospital.After the recording station answers, he would then dial in (or if atouch tone telephone, punch the buttons on the touch tone telephone) toenter the patient identification number, his date of birth, sex, height,weight, any clinical data code, and date and time at which thecardiogram was being taken. All in all, the technician might have topunch the button some 24 times to enter the 24 items of information. Thedrawbacks of doing this manually are several. First, the chance of errorin making more than 24 dials is considerable. Moreover, the technicianhas no way of knowing if he has made a mistake in the dialing, due topushing the wrong button, or dialing the wrong number. Furthermore, thetime required to do the dialing or pushing the buttoms, is relativelyslow. The present invention avoids these shortcomings of the prior artby providing a means and methods of reducing human error enteringpatient identification information, and which also makes more efficientuse of the transmission and recording facilities used in medicalelectronics.

According to an embodiment of the present invention, a unit is providedin which a technician enters the patient identification information fromthe patient or from his chart. The unit includes means for displayingthe entered information. After reviewing the entered information, thetechnician may actuate the transfer of the information to a remotestation. This transfer is made at a speed consistent with the electricalcapabilities of the transmitting line, and the recording medium. Thetransmittal of the patient identification information would beimmediately followed by the automatic sensing and transmittal of theclinical information. In one embodiment the identification informationis continuously displayed to the technician. Should it be discovered,that an error has been made in the identification information, he canthen easily correct the identification information and retransmit italong with the clinical information.

it is an object oof the present invention to provide a novel method andmeans of minimizing error in the entry of patient identificationinformation which accompanies clinical information.

It is a further object of the present invention to provide a novelmethod and means for the efficient use of recording facilities and/orthe transmission facilities used in medical electronics.

According to the invention, there is provided an ap paratus fortransmitting clinical information concerning a patient's medicalcondition having means for entering patient identification informationinto a memory; means for displaying the patient identificationinformation stored in the memory, and means for transmitting the patientidentification information with the clinical information.

According to the invention, there is also provided a method of reducingerror in entering electrically represented patient identificationinformation which accompanies separately originated electricallyrepresented clinic patient information comprising the steps of enteringthe patient identification information into a memory, displaying theentered information, and transmitting the information in the memory.

The construction of an illustrative embodiment as well as furtherobjects and advantages thereof, will become apparent when read inconjunction with the accompanying drawings wherein:

FIG. 1 is a block diagram of an automatic medical data acquisition unitshowing an embodiment of the invention.

FIG. 2 is a plane view of a typical control panel of the patientidentification information apparatus.

FIG. 3 is a partial isometric and schematic view of a dial shown in FIG.2.

FIG. 4 is a schematic view of the patient identification informationapparatus.

FIG. 5 is a table of the relation between tones and numbers representedby two tone signals.

FIG. 6 is a schematic drawing of a manually operated switch in whichpatient identification information may be entered.

FIG. 1 shows in block diagram form, an automatic electrocardiograph dataacquisition unit having an apparatus of this invention. The operation ofthe unit as a whole may be very briefly reviewed as follows. At the lefthand side there is schematically shown 14 leads or electrodes 10 whichare connectable to a patient. The electrodes are connected through abuffer 18 to a matrix 20 which generates the twelve standard ECG leadsor waveforms as well as three waveforms of the Frank Orthogonal System.These outputs are provided three at a time to an output 12 shown here(right hand side of the drawing) as a telephone line, for transmissionto a remote diagnostic center or a remote recording unit (not shown). Atthe same time, the outputs of the amplifiers 23, 24 and 25 are fed to athree-channel chart-writer (not shown) to provide a visual record of thepatients cardiogram. The unit also includes a patient identificationapparatus shown generally by the legend 13. At the time of attaching theelectrodes 10 to the patient, the medical technician would also enterinto the patient identification apparatus 13, information as to thepatients name or identification number, the date, clinical data, ifappropriate, patients age, his sex, height, weight, and the time thatthe cardiogram is being taken. Apparatus 13 would then provide anoptical display of the information so entered and when the dataacquisition unit commences operation, the entered data in the patientidentification apparatus is transferred to the output 12.

Referring now to the elements in FIG. I in detail, the fourteenelectrodes 10 have the legends RA, LA, RL, LL, V,, V,, V V V,, V,, H, M,I, and E. These legends identify the location on the patients body wherethe electrode is attached. Namely, RA for right arm, LA for left arm, RLfor right leg, LL for left leg. The next six electrodes V to V. areconnected to the six precordial or chest points from which the chestmeasurements are derived. The electrodes identified H, M, I and E areconnected respectively to the right or left side of the neckposteriorly; to the center of the spine opposite to the chest leads; tothe right mid-axillary line at fifth intercostal space; and to the midsternum at the level of the fifth intercostal space of the patient toprovide the Frank Orthogonal measurements. The outputs from theelectrodes 10 are applied to a buffer 18 which for example, presents ahigh impedance to the electrodes and a low impedance to the next stagematrix 20. The buffer 18 typically consists of fourteen unity gainamplifiers with an input impedance of ten megohms shunted by 470 pfcapacitance. The outputs from the buffer are applied to matrix 20 whichgenerates the twelve output electrocardiogram leads or waveforms and thethree Frank Vector waveforms. The leads or waveforms generated in theelectrocardiogram group are the three standard limbleads I, ll, 11]; thethree aV leads; and the six V leads from l-6 inclusive. The three FrankVector waveforms, X,Y,Z, are also generated. A sequencer 22 is connectedto tthe matrix 20 and successively gates three of the leads or waveformsto output amplifiers 23, 24, and 25. For example, in a first timeinterval which typically might be six seconds in duration, the threestandard limbleads, 1, ll, III are applied respectively to amplifiers23, 24 and 25. The sequencer 22 would then cause a marker signal ofapproximately 1/10 second duration to be applied to the threeamplifiers, after which the sequencer would cause the three generated aVleads or waveforms to be applied respectively to the amplifiers 23, 24and 25 for a time duration of approximately 6 seconds, after which aspacer signal of one-tenth second would again be applied to the threeamplifiers, after which the first three of the six V leads or waveformsis applied, from the matrix 20 to the amplifiers etc. After the 15generated leads or waveforms, three at a time, have been passed to theamplifiers, a marker signal is applied afterwhich a calibration signalof known time duration and voltage amplitude is added. The amplifiedleads or waveforms from amplifiers 23, 24 and 25 are shaped as requiredfor the particular transmission system and are applied to three voltagecontrolled oscillators 27, 28 and 29. Each oscillator has a carrierfrequency compatible with voice transmission on a telephone line; andtypically oscillator 27 has a carrier frequency of 1,075 Hertz,oscillator 28 has a carrier frequency of 1,935 Hertz, and oscillator 29has a carrier frequency of 2,365 Hertz. The incoming signals or leadsfrom the amplifiers 23, 24 and 25 frequency modulate the carriers of theoscillators. The frequency modulated output signals from the oscillatorsare then applied to a mixer 30 which combines the signals on a singlelead 31. The signal is sent to a directional coupler 42; which forexample, is a hybrid transformer of a kind adapted to pass signals inone direction of a given frequency range, and to pass signals in theother direction of a selected frequency range. The combined frequencymodulated signals from the mixer 30 pass through directional coupler 42and go out over telephone line 12 to a remote recording station orremote diagnostic station. Alternatively, the directional coupler 42 maybe replaced by a tape recorder for making a tape recording of thefrequency modulated and mixed signals. The entire patient clinicalinformation is sensed, generated, and transmitted in less than 1 minute.

The directional coupler 42 passes incoming signals from the telephoneline 12 to a filter 44 and a lamp 46, provided the signals are in apredetermined frequency range (e.g. typical frequencies; 385 and 445Hertz). The incoming signals from the telephone line are warningsindicating that the remote receiving unit is not in a condition forreceiving information or the information source is not operatingproperly.

Patient identification is provided from an apparatus shown generally bylegend 13. It includes a manually operable control 50 connected betweena scanner 5! and a group of oscillators 52. The front panel of thecontrol 50 is shown in detail in FIG. 2. On the face of the panel thereis a plurality of thumb-wheel operatoroperable dials 54. In FIG. 2 thereis shown 36 dials 54, arranged in three rows. Each one of the dials 54is arranged to take any one of it) possible positions and each dial 54has a knob 55 adapted to be turned by an operator. A group of legendsnumbered 0 through 9 are mounted on the dial next to the knob and anyone legend may be displayed in a window 57. The different positions ofthe dial, the positions of the window and the location of the legends onthe dial are so arranged that one of the legends will appear on thewindow for each different position on the dial.

In the drawing, the first knob is at position 1 with the number 1displayed in the window 57. The technician operating the ECG dataaccumulation unit will turn the knob 55 of the dials 54 on the frontpanel to enter information to identify the patient. A total of4l itemsof information make up the patient identification. Thirtysix items areentered by the manipulation of the knobs of the dials. A remaining fourare pre-wired and identify the machine being used. The last item is ascale signal and is controlled by the halfstand switch 58 on the controlpanel. When the switch 58 is in the standard" position all of thetransmitted ECG signals are full amplitude. However, for certainpatients, this magnitude is too large, and an antenuator (not shown) isconnected in the output line by operation of the standard half standswitch to reduce the effective magnitude of the transmitted signal by 50percent. When the switch 58 is in the half stand position, a signal istransmitted (as the 41st item of information) to indicate that the ECGhas been attenuated and that the receiving equipment should amplify thereceived signal by a factor of two to bring them up to their correctsize.

The 36 items of information entered manually on the dials can be seen inFIG. 2. The items of information are as follows: beginning with the toprow and progressing from left to right six positions for the patientidentification number; the next three are for clinical data; the nexttwo are for age; and one for sex. On the next line, the first threepositions are for height; then three positions for weight; and then sixpositions for the date month, day and year. On the third line, positionsare reserved for extra information and then the last two positions forthe hour at which the measurement is being made. Some of the informationwhich is entered here may also be used to provide a check or errordetection to insure that the operator has the correct patient. Forexample, if the patient identity number does not agree with his sex, orhis approximate height and weight, then there would be an indicationthat the data being accumulated is not that of the patient whoseidentity is being entered into the machine. Furthermore, a technicianwho enters the wrong day and wrong hour is apt to make other mistakes onentering the data, and is an indication to check further.

Referring now to FIG. 3 there is shown a partial isometric view of thedial 54 with legends 56 appearing in the window 57, connected by a shaftshown sche matically as 58 to a ten positon rotary switch 64. The switch64 has 10 fixed contacts 65 and a movable contact 66. The movablecontact 66 is mechanically linked by the shaft 58 to the rotary dial 54.When the dial 54 is moved from one of its positions to the next, tthemovable contact 66 makes electrical connection with different fixedcontacts corresponding to the different numbers being displayed in thewindow 57. The legends 0-9 next to the fixed contacts 65 indicate whichcontact is connected to movable contact 66 when the corresponding number0-9 is being displayed in the window 57.

FIG. 4 schematically shows the control 50, scanner 51 and oscillators 52in detail. In the previously given example, the patient identificationinformation includes forty-one items of information. The scanner 5] has4] information output leads and sequentially provides on each outputlead a pulse typically of 100 milliseconds duration. The scanner is a 48stage shift register 70 driven by a clock source 72. The output fromeach stage is provided on a different lead and the out put from the laststage is fed back to the clock 72 to block further pulses. The scanner51 is set in operation by a signal applied to a rest and start lead 73.Thirty-six of the outputs from the shift register 70 are connected tothe 36 switches 64; four outputs are connected through fixed wiring andone output is connected to the half stand switch 58. The outputs fromthe switches 64, fixed wiring and switch 58 are applied to matrix 82 andthen to a group of tone oscillators 52 for transmission. It might behelpful here to next examine the tone oscillators. The recording orreceiving equipment (not shown) which receives the information from theunit, is of the kind adapted to receive identification and supervisoryinformation as a simultaneous two-tone signal. This kind of signal iscommonly used in touch tone telephone dialing. For those unfamiliar withthis method of signaling, the following brief description may behelpful. Each item of information, which here is a number from 0 through9 (and two command signals identified as a star and a diamond is made upof two simultaneous tones. For example, the number 1 is represented by atone of 697 Hertz simultaneous with a tone of 1,209 Hertz. The number 2is represented by the two tones of 697 Hertz and 1,336 Hertz. Tonesensitive decoders receive these two tone signals to provide informationas to the number it represents. The sources of the tones are typicallytwo oscillators taped at four and three frequencies respectively, andactivated in pairs to indicate the number. The oscillators are shown inFIG. 4 (for simplicity) as seven separate oscillators Fl through F7. Itwill be appreciated that seven tones may be combined two at a time toproduce 12 different combinations of pairs of tones.

FIG. 5 is a table showing the number representations 1, 2, 3, 4, 5, 6,7, 8, 9, 0, arranged in rows and columns. Above each column and to theleft of each row, is listed the frequency of the tones that are combinedto represent the number appearing at the intersection of a particularrow and column. For example, the number 1, first row and first column,is made up of the two tone signals of 697 Hertz and L209 Hertz. Two isrepresented by 697 Hertz and 1,336 Hertz, etc.

ln the table, there is also shown the legends F1 through F7 associatedwith various rows and columns. These numbers designate the oscillatorswhich provide the signals at the associated tone. For example, the F1oscillator will provide a signal of 697 Hertz. The (F4 and FS; 942 Hertzand L209 Hertz) and the (F4 and F7; 942 Hertz and 1,477 Hertz) are usedas command signals to initiate, terminate and space operation of theremote recording or of diagnostic equipment (not shown).

Referring again to FIG. 4, the oscillator 52 includes seven oscillators,Fl F7 which provide, when activated, the tones required for two tonesignaling. The oscillators are connected to a coding matrix 82 having l2input leads corresponding to the numbers -9, and The coding matrix 82 isinterconnected such that when an input signal is applied for example, onthe l lead, L-l, the oscillators F1 and F5 are energized. This will beappreciated by tracing the connection from the one lead L-l to theoscillators F1 and F5. Likewise, an input on any other of the leads L-lthrough L-0 and L" and L will cause actuation of the appropriate pair oftone oscillators F-l through F-7 that represent that number with whichthe lead is associated. Ten of the twelve outputs L-l through L-0 areconnected to the corresponding fixed contacts 65 on each of tthe rotaryswitches 64, Le. the L-l input is connected to the 1" fixed contact ofeach of the 36 rotary switches 64, and the L-Z input is connected to the2" fixed contact of each of the 36 rotary switches 64, etc. Theconnections are shown schematically being made to only two of theswitches 64 but it is understood that the connections are made to alloof the switches. Thirty-six of the 41 output leads 74 of the scanner 51are connected respectively to the movable contact 66 of the switches 64.Thus, the output pulses from the scanner 51 are sequentially appliedthrough the movable contact 66 to the fixed contact 65 with which it isin contact and then to the matrix 82 which applies the pulse to activatethe two tone oscillators associated with the fixed lead through whichthe signal passes. The output two tone signal is determined by theposition of the rotary switch, which in turn is determined by theposition of the thumb knob 54.

The first or left most output from the scanner 5! is connected to the Llead. This is a control signal to indicate that the "patientidentification information is coming". The 38th through 4lst outputsfrom the scanner 5] (right hand side of the scanner) are connected byfixed wiring to leads L-9, L-l, L-3, L-0 of the matrix 82. Thisinformation or code (9130) represents the number of the machine. Eachmachine has a different number. Should a machine become faulty inoperation, all clinical information obtained from that machine may beidentified and reviewed for accuracy. The 42nd output is connected tothe half stand switch 58, whose function is defined above.

The remaining output leads (43rd through 48th) from the scanner 51 maybe connected (not shown) to the sequencer 22 to begin generation andtransmission of the patient clinical information immediately aftercomplete sending of the patient identification information. Finally, thelast output pulse (or the pulse after the last used pulse) is applied tothe clock 72 to turn off the clock and stop further pulses from theshift register.

The output from the two groups of oscillators F-l through F-4 andoscillators F5, F6 and F7 are combined and applied (via the mixer 30) tothe directional coupler 42 for transmission on output line 12.

An alternative embodiment to the dial 54 rotary switch 64 combination isto use a matrix switch as shown schematically in FIG. 6. The matrixswitch 90 has l2 output conductors 91 which are joined to the l2 leadsLl through L of the matrix 82. Switch 90 has 36 input conductors 92which are connected to the second through 37th outputs of shift register70. The conductors 91 and 92 are located adjacent to each other in acon-conducting electrical relation. Thirty-six manually operatedcontacts 93, such as sliders, are activated by the technician enteringthe patient identifcation information. There is one contact 93 for eachinput conductor 92. The contacts 93join each of the conductors 92 to anyone of the output conductors 91. There is shown schematically in thefigure a contact being made between the first of the conductors 92 andthe first of the output leads 9] which makes contact to the L1 lead onthe matrix 82. Alternatively (not shown) diodes can be used to provideisolation between positions in the matrix. This corresponds to the entryof the numeral 1 in the first position of the first item of patientidentification information (i.e. a l in the first number of the patientidentity). Contact is made by a manually operative contact knob locatedon the control panel of the patient signal dispatcher. A suitable matrixswitch of the kind described is manufactured by the Cherry ElectricalProducts Corp., Highland Park, Ill. Alternatively, any convenient orconventional matrix switch may be used.

Thus, there has been shown a data acquisition unit in which the patientidentification information is entered manually by a technician, and theinformation entered is displayed to the technician for him to check.When the ECG lead or other source of clinical information is ready, thetechnician causes the patient identification information displayed tohim, along with the clinical information, to be transmitted to arecording medium and transmitting line.

The above description of the invention is intended to be illustrativeonly, and various changes and modifications in the embodiment describedmay occur to those skilled in the art. These changes may be made withoutdeparting from the scope of the invention, and thus it should beapparent that the invention is not limited to the specific embodimentdescribed or illustrated in the drawings.

What is claimed is:

1. Apparatus comprising: means for receiving clinical informationconcerning a patient's medical condition; means for entering patientidentification information into a memory; optical display means fordisplaying the patient identification information entered; and means fortransmitting the displayed patient identification information with theclinical information.

2. Apparatus according to claim I, wherein the display means areoperator viewable and the transmitting means includes operator-operablemeans for initiating the transmission of the patient identificationinformation.

3. Apparatus according to claim 2, wherein the means for initiating thetransmission of the identification information also includes means forinitiating transmission of the clinical information immediately adjacentto the identification information.

4. Apparatus according to claim I, in which the means for enteringpatient identification information into the memory is a plurality ofmulti-position arrays with each position thereof corresponding to adifferent information character.

5. Apparatus according to claim 4 wherein the multiposition arrays aredials.

6. Apparatus according to claim 4 wherein the multiposition arrays arematrix switches.

7. Apparatus according to claim 4 further including a plurality ofdifferent tone sources; and means for selectively combining two tonesources into a two tone signal in accordance with the selected positionof the array.

8. Apparatus according to claim 5 wherein the means for transmitting thepatient identification information includes sequencing means forsequentially enabling the two tone signal which corresponds to the dialportion to an output.

9. Apparatus according to claim 4 wherein the means for displaying theinformation in the memory includes a plurality of informationcharacters, each character being associated with a particular positionon the array; and means for identifying the information characters inaccordance with the position of the array.

10. A method of reducing error in entering electrically representedpatient identification information which accompanies separatelyoriginated electrically represented patient clinical informationcomprising the steps of entering the patient identification informationinto a memory, displaying the entered information, and transmitting theinformation in the memory together with the clinical information.

i l I! t

1. Apparatus comprising: means for receiving clinical informationconcerning a patient''s medical condition; means for entering patientidentification information into a memory; optical display means fordisplaying the patient identification information entered; and means fortransmitting the displayed patient identification information with theclinical information.
 2. Apparatus according to claim 1, wherein thedisplay means are operator viewable and the transmitting means includesoperator-operable means for initiating the transmission of the patientidentification information.
 3. Apparatus according to claim 2, whereinthe means for initiating the transmission of the identificationinformation also includes means for initiating transmission of theclinical information immediately adjacent to the identificationinformation.
 4. Apparatus according to claim 1, in which the means forentering patient identification information into the memory is aplurality of multi-position arrays with each position thereofcorresponding to a different information character.
 5. Apparatusaccording to claim 4 wherein the multi-position arrays are dials. 6.Apparatus according to claim 4 wherein the multi-position arrays arematrix switches.
 7. Apparatus according to claim 4 further including aplurality of different tone sources; and means for selectively combiningtwo tone sources into a two tone signal in accordance with the selectedposition of the array.
 8. Apparatus according to claim 5 wherein themeans for transmitting the patient identification information includessequencing means for sequentially enabling the two tone signal whichcorresponds to the dial portion to an output.
 9. Apparatus according toclaim 4 wherein the means for displaying the information in the memoryincludes a plurality of information characters, each character beingassociated with a particular position on the array; and means foridentifying the information characters in accordance with the positionof the array.
 10. A method of reducing error in entering electricallyrepresented patient identification information which accompaniesseparately originated electrically represented patient clinicalinformation comprising the steps of entering the patient identificationinformation into a memory, displaying the entered information, andtransmitting the information in the memory together with the clinicalinformation.